"Over the last several days, the Chinese survey ship, Haiyang Dizhi 8, and its escorts have conducted activities in the southern area of the East Sea that have violated Vietnam’s Exclusive Economic Zone (EEZ) and Continental Shelf as established in the provisions of the 1982 United Nations Convention on Law of the Sea [UNCLOS], to which Vietnam and China are signatories," Foreign Ministry spokeswoman Le Thi Thu Hang said.

The East Sea is internationally known as the South China Sea.

Hang said Vietnam has contacted China on multiple occasions via different channels, delivered diplomatic notes to oppose China's violations and staunchly demanded that China stop all unlawful activities, withdraw its ships from Vietnamese waters and respect Vietnam's sovereign rights and jurisdiction over its waters, which would serve the interests of bilateral relations as well as regional stability and peace.

Vietnamese authorities at sea have employed a range of of appropriate measures to exercise Vietnam’s sovereignty, sovereign rights and jurisdiction in a peaceful and lawful manner for safeguarding Vietnamese waters, she added.

Hang last Tuesday emphasized strongly that it was Vietnam's consistent position to resolutely and persistently stand against any act infringing upon Vietnam’s sovereignty, sovereign rights and jurisdiction in Vietnamese waters established in the provisions of the 1982 UNCLOS through peaceful means in accordance with international law.

"All countries within and outside of the region share the common interest in maintaining order, peace and security in the East Sea. Therefore, in Vietnam’s view, all relevant parties and the international community should contribute to the joint effort to protect and ensure our common interest," she said.

Under the provisions of the 1982 UNCLOS, a coastal state has sovereign rights for the purpose of exploring, conserving and managing the natural resources, whether living or non-living, of the waters superjacent to the seabed and of the seabed and its subsoil, and with regard to other activities for the economic exploitation and exploration of its EEZ, which is within 200 nautical miles from the baseline.

As for its continental shelf, the coastal state has exclusive sovereign rights for the purpose of exploring it and exploiting its natural resources, and no one may undertake these activities without the express consent of the coastal state.